I have a yucca and it has developed green/blue patches and its stem and bark are soft to the touch. The leaves have all but fallen off as where they join seems wet consequently making them weak. My plant is dying can I save it and how?
I’m afraid your Yucca cannot be saved. Once a stem gets soft, it means the roots have rotted to such a degree that they are dead and non-functional and have been for quite a while.
The roots of Yuccas do not tolerate constantly damp soil around them so they are easy to inadvertently over water. Yuccas also require lots of direct sunlight and inadequate light will contribute to the plant’s demise. Finally, I will note that if you moved your Yucca into a new pot there is a good chance that contributed to the root rot.
Chalk this one up to a good learning experience. I hope you will not be discouraged from trying new plants in the future.